An attempt was made to observe the effect of rutile titanium dioxide nanoparticles( TiO_2 NPs) on oxidative damage of zebrafish( Danio rerio). Adult zebrafish was exposed to TiO_2 NPs at the concentrations of 10,50 and 100 mg·L~(~(-1)) for 10 days with the exposure to the bulk TiO_2( 100 mg·L~(~(-1))) as the control. Twenty adult zebrafish were treated at each concentration,and six fish treated were caught to analyze their changes of superoxide dismutase( SOD) activities in the gills,livers and guts. The SO...